Third: We know that a urolith lab is currently conducting a study of
cystine uroltihs specifically because the rate of these bladder
stones/kidney stones has increased markedly in the last year *.  Cystine
stones are formed when certain building blocks of protein are too high in
the diet (either cystine alone or in conjunction with members of the COLA
group of amino acids: cystine, ornithine, lysine, and arginine) so high
protein diets can push susceptible mammals over the top.  In the U.S. a
long history of ~35% protein diet could have failed to cause the early
deaths of ferrets with this type of genetic susceptibility (if they are
among the multiple domestic and wild mammals -- including other members
of Carnivora who have a certain genetic kidney flaw in regard to these
protein building blocks) resulting in them being in a higher % of the
population than early die-offs would have permitted in places where high
protein diets are traditionally used.  And don't fail to realize that
such stones can and do cause early die-offs especially in the males who
can block with smaller stones than the females.  (Historically in the
U.S. Cystine stones have not been as common as struvite stones in
ferrets.  Struvite stones are caused by a high percentage of vegetable
matter in the diet so be careful to think accordingly in relation to the
really cheap treats and cheap food.  (Unfortunately, when stones happen
some vets just assume that they will turn out to be struvite and don't
test; since some aspects of the approaches to deal with these two types
of stones are the opposite for cystine as opposed to struvite the result
can be recurrence with all of its attendant risks.)
 
Just what ARE accurate rates in the U.S. of insulinoma and of cystine
stones on about 35% protein diets, and what are they on the higher
protein diets?  No one knows the rates so knowing any possible rate
change of either is impossible currently.  If there is a decrease in
insulinoma cases BUT an increase of cystine stones from the same dietary
change which change will turn out to involve more U.S.  ferrets?  Both
are serious medical problems which can be fatal.  Can the rate of cystine
stones be reduced by bringing in more breeders from areas of the world
with traditionally high protein diets?  This is hypothetically possible
depending on what is learned in study.  Meanwhile, if there is a genetic
susceptibility to insulinomas which has increased in the population from
breeding for fancies, how much can we reduce such vulnerabilities by
getting away from appearance-first breeding?  Also hypothetically
possible.  There right now aren't even the needed baseline numbers to
figure out current rates which is very frustrating.
 
Is there a genetic component to either of these medical problems?  (In
many mammals there is a genetic component for cystine stones, and there
were some postulated (but not funded) studies to try to check into the
existence of possible genetic factors for insulinoma (for instance, MEN
(multiple endocrinological neoplasia genetics), Kit genetics -- Kit is
the postulated more likely cause of neural crest genetic disorder
markings like the panda head or blaze head with body spotting and Kit
is a known oncogene, etc.)
 
How will the rates compare?  (Needed to know to understand if the
difference in diets is a win, in the noise, or maybe even a lose.) Are
there easily recognizable sub-populations which should be approached
differently even before either disease happens and if so how can they
be spotted?  We just do not know.
 
What are the KNOWN mechanisms involved?  It is important to outline the
gaps which happen to be many.
 
At what ages are these serious medical problems most often seen?  (We
already know that insulinoma is more likely to happen at an older age,
and it appears that the cystine stone problem is more diet related so we
know it can happen even in kithood if certain vulnerable ferrets have
high protein diets then.)
 
Might it at some point be possible in some future decade to economically
figure out which individuals have which vulnerabilities so that chosen
diet can reflect working around those?  That is probably the ultimate
best goal.  Meanwhile, don't feel guilty if you use a reputable diet of
any type which differs from what any else (including me) uses.  Guilt is
not productive.  Research to eliminate gaps is.
 
*Dr. Michelle Hawkins VMD DABVP (Avian) is coordinating this effort and
can be reached at: 2108 Tupper Hall, University of CA, Davis, CA 95616,
1-530-752-1363 (phone) <[log in to unmask]>
[Posted in FML issue 4777]